{"instruction": "You are an expert in named entity recognition. Please extract entities that match the schema definition from the input. Return an empty list if the entity type does not exist. Please respond in the format of a JSON string.", "schema": ["Disease", "Chemical"], "input": "Systemic pretreatment with ketanserin , a relatively specific type - 2 serotonin receptor antagonist , significantly attenuated the muscle rigidity produced in rats by the potent short - acting opiate agonist alfentanil ."}
{"Disease": ["muscle rigidity"], "Chemical": ["ketanserin", "serotonin", "alfentanil"]}